The Worcester Porcelain Factory was founded in 1751 by Dr John Wall, Royal Worcester marks incorporating a crown above a circle were first introduced in 1862 and combined the number 51 within the circle signifying the year Dr Wall founded the original company.
This printed mark was used in may colours, often puce, green or blue in earlier pieces, mostly black marks were used from around 1950 to the mid 60's. Date codes or marks were nearly always used alongside the standard mark up until 1966 when a different format of back-stamp was introduced. The more modern items, from the late 60's onwards, mostly used black or gold back-stamps.
Between the years of 1862 and 1875 the last two numbers of the the years were occasionally used to indicate the year of manufacture but in 1867 a more organised method of date codes was introduced, with a letter beneath the standard mark, 1867 used the letter A, 1868 used B, 1869 C and so on.
In 1891 Royal Worcester introduced the words 'Royal Worcester England' beneath the standard Worcester mark with the addition of a dot to the left of the crown in 1892, followed by a further dot to the right of the crown in 1893, and this continued until 1903 with a total of twelve dots, six either side of the crown. In 1904 further dots (one for each additional year) were added beneath the words 'Royal Worcester England', until 1915 with a total of 24 dots, six dots either side of the crown and twelve beneath the words 'Royal Worcester England'.
The method of using an additional dot for each year was becoming rather cumbersome, so in 1916 a small star was used below the standard mark with the addition of a dot for each preceding year. This method was used until 1927 when there were eleven dots arranged around the single small star.
From 1928 Royal Worcester introduced a different shape as the date code for each preceding year, until 1933, when they started the method of adding an additional dot for each year. This method continued until 1941 when there were nine dots arranged around three interlinked circles.
Between the years of 1942 and 1948 no date codes were used. In 1949 the letter V was used and in 1950 W was used, in 1951 the method of adding an additional dot for each year either side of the W was reintroduced. From 1956 the letter R was often used in place of the W. This method continued until the mid 60's and from 1966 the date code was rarely used.
With the introduction of the more modern bone china table wear the year of the introduction of the pattern was used rather than the year of the individual pieces manufacture. The more decorative pieces, not designed for everyday use, often used a mark with no date code or manufacture year.